Europe Technologies Group

Shot Peening ?


J. Almen discovered SHOT PEENING while working at General Motors in the 1930's.

Shot peening is a process used to produce a beneficial compressive residual stress layer and modify mechanical properties of metals. Shot peening entails impacting a surface with high velocity shot (round metallic, glass or ceramic beads) with force sufficient to create plastic deformation: each bead functions as a tiny peening hammer.
Shot peening a surface spreads it plastically, causing changes in the mechanical properties of the surface. Shot peening is often called for in sensitive parts repairs to relieve tensile stresses built up in the grinding process and replace them with beneficial compressive stresses. Depending on the part geometry, part material, shot material, shot quality, shot intensity, shot coverage, shot peening can increase fatigue life from 0%-1000%.
Surface compressive stresses confer resistance to metal fatigue and to some forms of stress corrosion.


Conventional methods for propelling shot media include air blast systems and centrifugal blast wheels. Other methods include ultrasonic peening, wet peening, and laser peening (which does not use media).


SONATS is mastering Ultrasonic Shot Peening technology which offers proven advantages.